by A. Watts, Mar 25, 2023 in WUWT
Originally posted at ClimateREALISM
The Intergovernmental Panel on Climate Change (IPCC) published the final part of its sixth assessment report (AR6) on Monday, March 20. Predictably, the media rushed to repeat the claims made in the report with their own scary, woefully overwrought, headlines. Here is a sample: The Washington Post – World is on brink of catastrophic warming, U.N. climate change report says; NBC News – Now or never: One of the biggest climate reports ever shows time is running out; The Guardian – Scientists deliver ‘final warning’ on climate crisis: act now or it’s too late; and finally Inside Climate News, with inarguably the worst headline New IPCC Report Shows the ‘Climate Time Bomb Is Ticking,’ Says UN Secretary General António Guterres.
Each of mainstream media outlets predict that “climate doom” is just around the corner, and they’re all wrong.
The reason? The newest IPCC report laments the fact that Earth will soon pass the 1.5°C level of temperature rise, seen in the projection in Figure 1. The current extrapolation is to reach 1.5°C by April 2035.
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Based on that projection, the IPCC and the media predict very bad things will happen if we don’t “act now before it’s too late.” The most recent report in the AR6 series contains no new information, rather it reiterates the warnings made the physical science portion of the report issued in the summer of 2021, which also mentioned approaching 1.5°C.
Interestingly, the “before it’s too late” language has been used since 2005, when worry about just 1°C was the big doomsday news:
NASA scientist Jim Hansen introduced the “too late” language about climate change in 2005, arguing that “We have to stabilize emissions of carbon dioxide within a decade, or temperatures will warm by more than one degree [C]… we don’t have much time left”.
We heard the same type of language in 2007, when the IPCC released their Fourth Assessment Report. The headlines in The Guardian said “time is running out” and warming “could be irreversible.”
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by R. Pielke Jr., Mar 23, 2023 in ClimateChangeDispatch
The Intergovernmental Panel on Climate Change (IPCC) is an important institution. I have often said that if it did not exist, it would have to be invented. The IPCC is often referred to as a model for how to do a scientific assessment.
Consequently, we should have the highest standards for evaluating its work, not least because climate change is important, and effective mitigation and adaptation policies are essential. [emphasis, links added]
Below I share a brief few critiques of the culminating report of the current IPCC cycle, called the Synthesis Report. The new report covers six IPCC reports published over the past nine years.
Before proceeding, it is crucial to understand that the IPCC is not a single entity or group of people. It is many different groups doing many different things, with many strengths — for instance, WG1 on extremes was particularly good.
The IPCC also has some notable weaknesses — its reliance on out-of-date scenarios most obviously. The Synthesis Report was written by a small group of people.
For better or worse, the work of this small group of people reflects upon the entire IPCC and the years of effort leading to this week’s report.
If I were an IPCC participant not involved with the Synthesis Report, I’d be pretty upset. My view is that the IPCC has strayed far from its role to assess the scientific literature in support of policymaking.
It has increasingly taken on a stance of explicit political advocacy and as it does so it has ignored and even misrepresented relevant science.
The IPCC needs a complete overhaul.
Below are some more detailed thoughts on the Synthesis Report.
Scientific Assessment Minus the Science
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by P. Ridd, Mar 2023 in Clintel
VIDEO (41 min)
by P. Stallinga, Mar 23, 2023 in NoTricksZone
Since the early 1990s the conventional assumption, aligned with modeling, has been that a molecule of human CO2 emission stays in the atmosphere – its residence time – for centuries. This fits the anthropogenic global warming (AGW) narrative. But empirical evidence contradicts these model-based assumptions. Residence time is closer to 5-10 years.
In Table 1 of a new study, Stallinga (2023) compiled a list of 36 published estimates of CO2 residence time spanning the decades 1957-1992. All of these scientists determined CO2’s atmospheric residence time is about 5 to 10 years or less.
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Of course, these were the pre-IPCC decades in climate research, when “the science” was pursued independent of government interference. For example, it was still acceptable in the 1950s to early 1990s for scientists to publish actual ice core measurements showing the atmospheric CO2 content ranged up to 700 ppm, even 2,450 ppm, in the ice sheets and glaciers examined throughout the last 10,000 years (Jaworowski et al., 1992).
An actual residence time that is 20 to 40 times shorter in duration than what an AGW modeled thought experiments allow undermines the dangerous greenhouse gas accumulation talking points, as “if the residence time is below 30 years, injections of CO2 in the atmosphere would, just as water, not affect the climate” (Stallinga, 2023).
In addition to compiling an exhaustive list of past estimates supporting a 5-10 year residence time, Dr. Stallinga cites the evidence from atomic bomb tests, the lack of any atmospheric CO2 effect from the pandemic lockdowns and associated sharp drop in emissions, and the lead-lag relationship CO2 emission has with temperature as evidence supporting the once commonly-accepted conclusion that CO2 residence is closer to 5 years, not centuries.
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